The purpose of this hack is to remove stage difficulty scaling. So you can choose a Game Level (easy, normal, hard, arcade) that does not surreptitiously overwhelm you, and does give you better chances of recovering when you die.
(While each Game Level is easier than in the unmodded game, be assured that Normal Level, for instance, is still harder with this hack than Easy Level without it. ^^ )
ROM / ISO Information:
Gradius III (USA)
No-Intro: Super Nintendo Entertainment System (v. 20180813-062835)